U.S. patent number 10,604,731 [Application Number 15/695,633] was granted by the patent office on 2020-03-31 for cell analyzer, cell analyzer controlling method, and program.
This patent grant is currently assigned to SYSMEX CORPORATION. The grantee listed for this patent is Sysmex Corporation. Invention is credited to Shigeki Iwanaga, Takuya Kubo, Kanako Masumoto, Masaya Okada.
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United States Patent |
10,604,731 |
Masumoto , et al. |
March 31, 2020 |
Cell analyzer, cell analyzer controlling method, and program
Abstract
Provided is a cell analyzer including: a light source unit
configured to apply light to test cells each containing first
substances which are bound to first fluorescent dyes and which
serve as an index for therapeutic strategy judgement; an image
capturing unit configured to capture an image of fluorescence
caused by the light; a processing unit configured to process the
image obtained by the image capturing unit; and a display unit
configured to display a process result obtained by the processing
unit, wherein the processing unit obtains a first image by
performing an inactivation process of quenching the first
fluorescent dyes, an activation process of activating a part of the
first fluorescent dyes that have been quenched, and an image
capturing process of capturing, by means of the image capturing
unit, an image of the fluorescence by applying light from the light
source unit to each test cell; extracts bright points based on the
first fluorescent dyes on the basis of the first image; classifies
the extracted bright points into groups each corresponding to one
first substance, thereby to obtain the number of the first
substances in the test cell on the basis of the number of the
classified groups; obtains therapy index information serving as an
index for therapeutic strategy judgement, on the basis of the
obtained number of the first substances; and causes the display
unit to display the obtained therapy index information.
Inventors: |
Masumoto; Kanako (Kobe,
JP), Kubo; Takuya (Kobe, JP), Iwanaga;
Shigeki (Kobe, JP), Okada; Masaya (Kobe,
JP) |
Applicant: |
Name |
City |
State |
Country |
Type |
Sysmex Corporation |
Kobe-shi, Hyogo |
N/A |
JP |
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Assignee: |
SYSMEX CORPORATION (Hyogo,
JP)
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Family
ID: |
56876338 |
Appl.
No.: |
15/695,633 |
Filed: |
September 5, 2017 |
Prior Publication Data
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Document
Identifier |
Publication Date |
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US 20170362553 A1 |
Dec 21, 2017 |
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Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
Issue Date |
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PCT/JP2016/055947 |
Feb 26, 2016 |
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Foreign Application Priority Data
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Mar 6, 2015 [JP] |
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2015-045320 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
G06T
7/0012 (20130101); C12M 1/34 (20130101); G01N
33/5005 (20130101); G01N 21/6428 (20130101); G06K
9/00134 (20130101); G01N 21/6456 (20130101); G01N
21/64 (20130101); G06K 9/00147 (20130101); G01N
2021/6441 (20130101); G01N 2021/6432 (20130101); G06T
2207/30072 (20130101) |
Current International
Class: |
C12M
1/34 (20060101); G06K 9/00 (20060101); G06T
7/00 (20170101); G01N 21/64 (20060101); G01N
33/50 (20060101); C40B 30/00 (20060101) |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
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101918816 |
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Dec 2010 |
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CN |
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2010-500563 |
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Jan 2010 |
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JP |
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2011-508214 |
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Mar 2011 |
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JP |
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2012-103077 |
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May 2012 |
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JP |
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5416582 |
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Feb 2014 |
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JP |
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2014-052746 |
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Mar 2014 |
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JP |
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2008/091296 |
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Jul 2008 |
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WO |
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WO 2009/085218 |
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Jul 2009 |
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WO |
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.pdf>. cited by applicant .
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Primary Examiner: Wecker; Jennifer
Attorney, Agent or Firm: Brinks Gilson & Lione
Parent Case Text
RELATED APPLICATIONS
This application is a continuation of International Application
PCT/JP2016/055947 filed on Feb. 26, 2016, which claims benefit of
Japanese patent application JP 2015-045320 filed on Mar. 6, 2015,
both of which are incorporated herein by reference in their
entireties.
Claims
What is claimed is:
1. A cell analyzer comprising: a light source unit configured to
apply light to a test cell of which a first substance is stained
with a first fluorescent dye; an image capturing unit configured to
capture an image of fluorescence caused by the light; and a
processing unit configured to process the image obtained by the
image capturing unit, wherein the processing unit is programmed to
obtain a first image by performing an inactivation process of
quenching the first fluorescent dye, an activation process of
activating a part of the first fluorescent dye that have been
quenched, and an image capturing process of capturing, by the image
capturing unit, an image of the fluorescence by applying light from
the light source unit to the test cells; wherein said processing
unit is programmed to extract bright points based on the first
fluorescent dye on the basis of the first image; and wherein said
processing unit is programmed to classify the extracted bright
points into groups each corresponding to one first substance,
thereby to obtain the number of the first substances in the test
cell on the basis of the number of the classified groups.
2. The cell analyzer of claim 1, wherein the processing unit
further obtains information regarding a distribution state of the
first substances.
3. The cell analyzer of claim 1, wherein the processing unit
further obtains information regarding location of the first
substances.
4. The cell analyzer of claim 1, wherein each first substance is a
gene that changes in a specific manner in a cell with a specific
disease or a protein that changes in a specific manner in a cell
with a specific disease.
5. The cell analyzer of claim 1, wherein each first substance is a
cancer marker gene or a cancer marker protein.
6. The cell analyzer of claim 1, wherein the light source unit
applies light to a test cell containing the first substance stained
with the first fluorescent dye; and second substance stained with a
second fluorescent dye that are different from the first
fluorescent dye, and the processing unit further obtains a number
of the second substance on the basis of a captured image of
fluorescence generated from the second fluorescent dye.
7. The cell analyzer of claim 6, wherein the processing unit
further obtains information regarding location of the second
substances.
8. The cell analyzer of claim 6, wherein the processing unit
obtains a therapy index information on the basis of a ratio between
the number of the first substances and the number of the second
substances.
9. The cell analyzer of claim 8, wherein the processing unit
determines presence/absence of change in the first substances on
the basis of the ratio between the number of the first substances
and the number of the second substances.
10. The cell analyzer of claim 6, wherein the first substance is
HER-2 gene contained in a nucleus of the test cell, and the second
substance is CEP17 contained in the nucleus of the test cell.
11. The cell analyzer of claim 6, wherein the processing unit
obtains a second image without performing an inactivation process
of quenching the second fluorescent dye, and counts the number of
the second substances in the test cell on the basis of the second
image.
12. The cell analyzer of claim 6, wherein the processing unit
obtains a second image by performing an inactivation process of
quenching the second fluorescent dye, an activation process of
activating a part of the second fluorescent dye that have been
quenched, and an image capturing process of capturing an image of
the fluorescence by applying light from the light source unit to
the test cell; and counts the number of the second substances in
the test cell on the basis of the second image.
13. The cell analyzer of claim 6, wherein the processing unit
obtains the first image and a second image by performing the
inactivation process of quenching the first fluorescent dye and an
inactivation process of quenching the second fluorescent dye, an
activation process of activating a part of the first fluorescent
dye that have been quenched and a part of the second fluorescent
dye that have been quenched, and an image capturing process of
capturing an image of the fluorescence by applying light from the
light source unit to the test cell; and counts the number of the
second substances in the test cell on the basis of the second
image.
14. The cell analyzer of claim 1, wherein the processing unit
performs a first processing step in which, before the first image
is obtained, a process of quenching and reactivating the first
fluorescent dye is performed once, then the first image of the
first fluorescent dyes is obtained, and a determination index
indicating presence/absence of change in the first substances is
obtained on the basis of the obtained first image; when the change
in the first substances obtained in the first processing step is
negative, causes a display unit to display the determination index
obtained in the first processing step, as therapy index
information; when the change in the first substances obtained in
the first processing step is not negative, performs a second
processing step in which the first image is obtained by performing
the inactivation process, the activation process, and the image
capturing process, and the number of the first substances is
obtained by performing a process of extracting the bright points
and classifying the bright points with respect to the obtained
first image.
15. The cell analyzer of claim 1, wherein the processing unit
performs an activation process of activating the first fluorescent
dye from a quenched state, by applying light having a predetermined
wavelength.
16. The cell analyzer of claim 1, wherein the processing unit
further causes a display unit to display an image indicating a
distribution state of the bright points of the first fluorescent
dyes.
17. The cell analyzer of claim 1, wherein the image capturing unit
is configured to obtain, with respect to each first fluorescent
dye, a captured image that allows identification of a position in
an optical axis direction as well as a position on a
two-dimensional plane at an image capture angle, and the processing
unit extracts bright points of a plurality of the first fluorescent
dye on the basis of the positions on the two-dimensional plane and
the positions in the optical axis direction, and classifies the
extracted bright points into groups each corresponding to a first
substance, thereby to obtain the number of the first
substances.
18. The cell analyzer of claim 1, wherein a nucleus of the test
cell is stained by third fluorescent dyes, and the processing unit
identifies a region of the nucleus in the test cell on the basis of
a captured image of fluorescence generated from the third
fluorescent dye, and obtains the number of the first substances for
each identified region.
19. A cell analyzer controlling method comprising: obtaining a
first image by performing an inactivation process of quenching
first fluorescent dye bound to one or more first substances in a
test cell, an activation process of activating a part of the first
fluorescent dye that have been quenched, and an image capturing
process of capturing an image of fluorescence by applying light to
the test cell; extracting bright points based on the first
fluorescent dye on the basis of the first image; and classifying
the extracted bright points into groups each corresponding to one
first substance, thereby to obtain the number of the first
substances in the test cell on the basis of the number of the
classified groups.
20. A non-transitory computer-readable computer medium storing a
program for causing a computer of a cell analyzer to perform
operations, wherein said program is programmed to: obtain a first
image by performing an inactivation process of quenching a first
fluorescent dye, an activation process of activating a part of the
first fluorescent dye that have been quenched, and an image
capturing process of capturing an image of the fluorescence;
extract bright points based on the first fluorescent dye on the
basis of the first image; and classify the extracted bright points
into groups each corresponding to one first substance, thereby to
obtain the number of the first substances in a test cell on the
basis of the number of the classified groups.
21. A cell analyzer comprising: a light source configured to
irradiate light onto a test cell of which a first substance is
stained with a first fluorescent dye; an imaging device configured
to capture an image of the test cell; and a processing unit
programmed to: repeatedly quench and activate the first fluorescent
dye in the test cell; cause the imaging device to capture a
plurality of images of the test cell under an irradiation by the
light source while quenching and activating; extract one or more
bright points in the images; and quantify a number of the first
substance residing in the test cell based on the extracted bright
points.
22. A cell analyzer comprising: first and second light sources
configured to irradiate light with different wavelengths onto a
test cell of which a first substance is stained with a first
fluorescent dye; an imaging device configured to capture an image
of the test cell; and a processor programmed to: cause the first
light source to irradiate light onto the test cell to activate the
first fluorescent dye in the test cell; cause the second light
source to irradiate light onto the test cell to quench the first
fluorescent dye in the test cell; cause the imaging device to
capture a plurality of images of the test cell in the course of
quenching during the irradiation by the second light source; merge
the images; and quantify a number of the first substance residing
in the test cell based on the merged image.
Description
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a cell analyzer, a cell analyzer
controlling method, and a program to be executed by a computer of a
cell analyzer.
2. Description of the Related Art
In certain diseases, specific genes, specific proteins, and the
like are involved in the progress of disease conditions. To confirm
the presence and the state of a specific substance with regard to
cells collected from a subject is very useful when making
determination of diagnosis and a therapeutic strategy for such a
disease.
For example, in the case of breast cancer, HER-2 gene which is a
prognostic factor is amplified in accordance with progress of the
disease condition. In Japanese Laid-Open Patent Publication No.
2012-103077, amplification of HER-2 gene is analyzed by use of a
FISH method. Specifically, a nucleic acid probe (HER-2 probe) that
binds to DNA of HER-2 gene and a nucleic acid probe (CEP17 probe)
that binds to the centromere region of chromosome 17 (CEP17) are
labeled with different kinds of fluorescent dyes, respectively, and
fluorescence that occurs from each probe in one cell is counted.
Then, when the ratio of the number of fluorescence from HER-2 gene
relative to the number of fluorescence from CEP17 is higher than or
equal to a predetermined value, amplification of HER-2 gene is
determined as positive, and when the ratio is less than the
predetermined value, amplification of HER-2 gene is determined as
negative.
In the above diagnostic approach, for diagnosis, an image
indicating the distribution state of fluorescence is provided to a
doctor or the like, for example. The doctor or the like is required
to perform complicated work such as making determination on the
disease condition while referring to the provided image. In
addition, in the diagnostic approach above, the provided image is
confirmed through visual observation to determine the disease
condition. Thus, the doctor or the like is required to be well
skilled in the determination, and the diagnoses could vary
depending on the person who makes the determination.
SUMMARY OF THE INVENTION
The scope of the present invention is defined solely by the
appended claims, and is not affected to any degree by the
statements within this summary.
A cell analyzer according to a first mode of the present invention
includes: a light source unit configured to apply light to test
cells each containing first substances which are bound to first
fluorescent dyes and which serve as an index for therapeutic
strategy judgement; an image capturing unit configured to capture
an image of fluorescence caused by the light; a processing unit
configured to process the image obtained by the image capturing
unit; and a display unit configured to display a process result
obtained by the processing unit. The processing unit obtains a
first image by performing an inactivation process of quenching the
first fluorescent dyes, an activation process of activating a part
of the first fluorescent dyes that have been quenched, and an image
capturing process of capturing, by means of the image capturing
unit, an image of the fluorescence by applying light from the light
source unit to each test cell; extracts bright points based on the
first fluorescent dyes on the basis of the first image; classifies
the extracted bright points into groups each corresponding to one
first substance, thereby to obtain the number of the first
substances in the test cell on the basis of the number of the
classified groups; obtains therapy index information serving as an
index for therapeutic strategy judgement, on the basis of the
obtained number of the first substances; and causes the display
unit to display the obtained therapy index information.
A second mode of the present invention relates to a cell analyzer
controlling method. The cell analyzer controlling method according
to this mode includes: obtaining a first image by performing an
inactivation process of quenching first fluorescent dyes bound to
first substances which are contained in a test cell and which serve
as an index for therapeutic strategy judgement, an activation
process of activating a part of the first fluorescent dyes that
have been quenched, and an image capturing process of capturing an
image of fluorescence by applying light to the test cell;
extracting bright points based on the first fluorescent dyes on the
basis of the first image; classifying the extracted bright points
into groups each corresponding to one first substance, thereby to
obtain the number of the first substances in the test cell on the
basis of the number of the classified groups; obtaining therapy
index information serving as an index for therapeutic strategy
judgement, on the basis of the obtained number of the first
substances; and displaying the obtained therapy index
information.
A non-transitory computer-readable computer medium storing a
program according to a third mode of the present invention is a
non-transitory computer-readable computer medium storing a program
for causing a computer of a cell analyzer to perform operations,
the cell analyzer being provided with a light source unit
configured to apply light to test cells each containing first
substances which are bound to first fluorescent dyes and which
serve as an index for therapeutic strategy judgement, an image
capturing unit configured to capture an image of fluorescence
caused by the light, and a display unit, the operations including:
obtaining a first image by performing an inactivation process of
quenching the first fluorescent dyes, an activation process of
activating a part of the first fluorescent dyes that have been
quenched, and an image capturing process of capturing, by means of
the image capturing unit, an image of the fluorescence by applying
light from the light source unit to each test cell, extracting
bright points based on the first fluorescent dyes on the basis of
the first image; classifying the extracted bright points into
groups each corresponding to one first substance, thereby to obtain
the number of the first substances in the test cell on the basis of
the number of the classified groups; obtaining therapy index
information serving as an index for therapeutic strategy judgement,
on the basis of the obtained number of the first substances; and
causing the display unit to display the obtained therapy index
information.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a diagram showing a configuration of a cell analyzer
according to Embodiment 1;
FIG. 2A is a diagram showing a state in which a first fluorescent
dye is bound to a first substance according to Embodiment 1;
FIG. 2B is a diagram showing a state in which a second fluorescent
dye is bound to a second substance according to Embodiment 1;
FIG. 3A is a diagram showing that all the first fluorescent dyes
are in an active state according to Embodiment 1;
FIG. 3B is a diagram showing that all the first fluorescent dyes
are in a quenched state according to Embodiment 1;
FIG. 3C is a diagram showing that a part of the first fluorescent
dyes are in an active state according to Embodiment 1;
FIG. 3D is a diagram showing that a part of the first fluorescent
dyes are in an active state according to Embodiment 1;
FIG. 4A is a flow chart showing an image obtaining process in a
first processing step according to Embodiment 1;
FIG. 4B is a flow chart showing an analysis process in a first
processing step according to Embodiment 1;
FIG. 5A is a diagram describing a procedure for obtaining a
reactivation diffraction-limited image and the number of substances
according to Embodiment 1;
FIG. 5B is a diagram describing a procedure of obtaining a
diffraction-limited image according to Embodiment 1;
FIG. 6A is flow chart showing an image obtaining process in a
second processing step according to Embodiment 1;
FIG. 6B is a flow chart showing an analysis process in a second
processing step according to Embodiment 1;
FIG. 7 is a diagram describing a procedure of obtaining a
super-resolution image and the number of substances according to
Embodiment 1;
FIG. 8A shows a positive reference image obtained in the first
processing step according to Embodiment 1;
FIG. 8B shows a positive reference image obtained in the first
processing step according to Embodiment 1;
FIG. 8C shows a positive reference image obtained in the first
processing step according to Embodiment 1;
FIG. 8D shows a positive reference image obtained in the first
processing step according to Embodiment 1;
FIG. 9A shows a positive reference image obtained in the second
processing step according to Embodiment 1;
FIG. 9B shows a positive reference image obtained in the second
processing step according to Embodiment 1;
FIG. 9C shows a positive reference image obtained in the second
processing step according to Embodiment 1;
FIG. 9D shows a positive reference image obtained in the second
processing step according to Embodiment 1;
FIG. 9E shows a negative reference image obtained in the second
processing step according to Embodiment 1;
FIG. 9F shows a negative reference image obtained in the second
processing step according to Embodiment 1;
FIG. 9G shows a negative reference image obtained in the second
processing step according to Embodiment 1;
FIG. 10A shows a positive reference image obtained in Comparative
Example 1;
FIG. 10B shows a positive reference image obtained in Comparative
Example 1;
FIG. 10C shows a positive reference image obtained in Comparative
Example 1;
FIG. 10D shows a positive reference image obtained in Comparative
Example 1;
FIG. 10E shows a positive reference image obtained in Comparative
Example 2;
FIG. 10F shows a positive reference image obtained in Comparative
Example 2;
FIG. 10G shows a positive reference image obtained in Comparative
Example 2;
FIG. 11 is a flow chart showing a display process according to
Embodiment 1;
FIG. 12A is a diagram showing a configuration of a screen displayed
on a display unit according to Embodiment 1;
FIG. 12B is a diagram showing a configuration of a screen displayed
on a display unit according to Embodiment 1;
FIG. 13 is a flow chart showing an image obtaining process in a
first processing step according to Embodiment 2;
FIG. 14A is a flow chart showing an image obtaining process in a
second processing step according to Embodiment 2;
FIG. 14B is a flow chart showing an analysis process in a second
processing step according to Embodiment 2;
FIG. 15A is a flow chart showing an image obtaining process in a
first processing step according to Modification of Embodiment
2;
FIG. 15B is a flow chart showing an image obtaining process in a
second processing step according to Modification of Embodiment
2;
FIG. 16A is a diagram showing a configuration of a cell analyzer
according to Embodiment 3;
FIG. 16B is a diagram showing rotation of two focal points on a
light receiving surface in accordance with the position of the
light emission point of fluorescence in the optical axis direction
according to Embodiment 3;
FIG. 17A is a diagram showing a three-dimensional super-resolution
image according to Embodiment 3;
FIG. 17B is a diagram showing a three-dimensional super-resolution
image according to Embodiment 3;
FIG. 17C is a diagram showing an image when a three-dimensional
super-resolution image is viewed in a Z-axis direction according to
Embodiment 3;
FIG. 17D is a diagram showing an image when a three-dimensional
super-resolution image is viewed in a Y-axis direction according to
Embodiment 3; and
FIG. 18 is a diagram showing a configuration of a screen displayed
on a display unit according to Embodiment 3.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
The embodiments below are obtained by applying the present
invention to a cell analyzer that obtains information regarding
breast cancer.
"Therapy index information" displayed by a cell analyzer is
information that serves as an index used by a doctor or the like
when deciding a therapeutic strategy such as administration,
surgery, or follow up. In the embodiments below, as one example of
the therapy index information, the number of HER-2 genes, which is
one of prognostic factors for breast cancer, is counted as the
number of first substances, and a determination result regarding
the ratio between the counted value and the number of CEP17s is
obtained and displayed as the therapy index information. On the
basis of this therapy index information, the doctor or the like can
confirm the state of HER-2 gene amplification. This enables, for
example, determination of an administration strategy as to whether
Herceptin (registered trade mark), whose generic name is
trastuzumab, and which is a molecular target drug whose specific
target is HER-2 gene, is to be used in a breast cancer therapy for
the patient. It should be noted that what is displayed by the cell
analyzer is not limited to the therapy index information described
above. The counted value of a disease marker which is the first
substances, the ratio between the first substances and second
substances, or the like may be outputted as "therapy index
information" which serves as an index when the progress state of a
disease relevant to the disease marker is to be determined.
1. Embodiment 1
As shown in FIG. 1, a cell analyzer 10 includes a light source unit
11, a shutter 12, a 1/4 wave plate 13, a beam expander 14, a
condenser lens 15, a dichroic mirror 16, an objective lens 17, a
stage 18, an image capturing unit 19, controllers 20, 21, and an
information processing apparatus 100. The image capturing unit 19
includes a condenser lens 19a and an image pickup device 19b. The
image pickup device 19b is a CCD, an EMCCD, a CMOS, or a scientific
CMOS image sensor, for example.
A glass slide 22 having a sample placed thereon is set on the stage
18. The sample includes test cells, and first substances and second
substances are included in the nucleus of each test cell. Each of
the first substances and the second substances to be detected is a
biogenic substance such as a gene, a protein, or a peptide which
serves as a disease marker, for example. Specifically, in
Embodiment 1, the test cells are collected from a lesion tissue.
The first substance is HER-2 gene and the second substance is the
centromere region of chromosome 17 (CEP17). HER-2 gene is a disease
marker for breast cancer. In normal cells, CEP17 is present by the
same number as that of HER-2 gene, and does not proliferate even
when the patient has breast cancer or the like. Thus, CEP17 is used
as an internal control which serves as a reference based on which
amplification of HER-2 gene is measured.
In a sample, first fluorescent dyes are bound to the first
substances, and second fluorescent dyes are bound to the second
substances. Each first fluorescent dye is switchable between an
active state in which the first fluorescent dye generates
fluorescence by being irradiated with light from a light source
11a, and an inactive state in which the first fluorescent dye does
not generate fluorescence even when irradiated with light from the
light source 11a. The first fluorescent dye is inactivated when
irradiated with light from the light source 11a, and is activated
when irradiated with light from a light source 11c. In the
following, "to inactivate" is referred to as "to quench". The
nucleus of each test cell is stained by third fluorescent dyes.
In Embodiment 1, by means of light from the light source 11c, the
first fluorescent dyes are activated from a quenched state. Light
from the light source 11c is also used to excite the third
fluorescent dyes to generate fluorescence. In this manner, since
light from the light source 11c can be used in common for
activation of the first fluorescent dyes and excitation of the
third fluorescent dyes, the configuration of the cell analyzer 10
can be simplified. Activation of the first fluorescent dyes may be
caused by the action of heat, chemical agent, or the like, instead
of the action of light.
The light source unit 11 applies light to each test cell. The light
source unit 11 includes the light sources 11a, 11b, 11c, and
dichroic mirrors 11d, 11 e. The light sources 11a, 11 b, 11c emit
lights having different wavelengths, respectively. As the light
source unit 11, a laser light source is preferably used, but a
mercury lamp, a xenon lamp, an LED, or the like may be used. The
dichroic mirror 11d allows light emitted from the light source 11b
to pass therethrough, and reflects light emitted from the light
source 11a. The dichroic mirror 11e allows lights emitted from the
light sources 11a, 11b to pass therethrough, and reflects light
emitted from the light source 11c. The optical axes of lights
emitted from the light sources 11a, 11 b, 11c are caused to be
aligned with one another by the dichroic mirrors 11d, 11 e.
Usually, the light sources in the light source unit 11 are
preferably arranged such that the wavelength of light emitted from
the light source 11b is longest, and the wavelength of light
emitted from the light source 11c is shortest.
The light source unit 11 applies light to each test cell, to cause
fluorescence to be generated from the test cell. Specifically,
lights emitted from the light sources 11a, 11b, 11c respectively
excite the first fluorescent dyes, the second fluorescent dyes, and
the third fluorescent dyes contained in the test cell to generate
fluorescence.
The shutter 12 is driven by the controller 20, and performs
switching between a state in which light emitted from the light
source unit 11 is allowed to pass therethrough, and a state in
which light emitted from the light source unit 11 is blocked.
Accordingly, the irradiation time period of light applied to the
test cell is adjusted. The 1/4 wave plate 13 converts linearly
polarized light emitted from the light source unit 11 into
circularly polarized light. A fluorescent dye reacts with light in
a predetermined polarization direction. Thus, by converting light
for excitation into circularly polarized light, the polarization
direction of the light for excitation can be easily aligned with
the polarization direction in which the fluorescent dye reacts.
Accordingly, each fluorescent dye contained in the test cell can be
efficiently excited to emit fluorescence. The beam expander 14
widens the light irradiation region on the glass slide 22. The
condenser lens 15 collets light such that collimated light is
applied to the glass slide 22 from the objective lens 17. The
shutter 12 and the 1/4 wave plate 13 may be arranged immediately
downstream of the light sources 11a, 11b, and 11c.
The dichroic mirror 16 reflects light emitted from the light source
unit 11, and allows fluorescence generated from the test cell to
pass therethrough. The objective lens 17 guides to the glass slide
22 the light reflected by the dichroic mirror 16. The stage 18 is
driven by the controller 21 and moves in a horizontal plane.
Accordingly, light is widely applied to the glass slide 22.
Fluorescence generated from the test cell passes through the
objective lens 17, and passes through the dichroic mirror 16. The
condenser lens 19a collets the fluorescence and guides the
fluorescence to the light receiving surface of the image pickup
device 19b. The image pickup device 19b captures an image of the
fluorescence and outputs the captured image.
The information processing apparatus 100 is a personal computer and
includes a body 110, a display unit 120, and an input unit 130. The
body 110 includes a processing unit 111, a storage unit 112, and an
interface 113.
The processing unit 111 is a CPU, for example. The storage unit 112
is a ROM, a RAM, a hard disk, or the like. The processing unit 111
performs various functions on the basis of programs stored in the
storage unit 112. The processing unit 111 processes images obtained
from the image pickup device 19b, and performs other various
processes. In addition, through the interface 113, the processing
unit 111 controls the light sources 11a, 11b, 11c of the light
source unit 11, the image pickup device 19b, and the controllers
20, 21. The display unit 120 is a display for displaying results
and the like of processes performed by the processing unit 111. The
input unit 130 is composed of a keyboard and a mouse for receiving
input of instructions from a user.
Hereinafter, a first processing step and a second processing step
performed by the processing unit 111 are described. In the
following, the captured images of fluorescences excited from the
first fluorescent dyes, the second fluorescent dyes, and the third
fluorescent dyes are respectively referred to as "first image",
"second image", and "third image". The wavelength, the intensity,
and the irradiation time period of each light described in the
explanation of the first processing step and the second processing
step are applied when the corresponding one of the first
fluorescent dyes, the second fluorescent dyes, and the third
fluorescent dyes is used in "(3) Experiment" described below. If
the first fluorescent dyes, the second fluorescent dyes, and the
third fluorescent dyes are changed, or if the dye labeling method
or the labeling density is changed, the wavelength, the intensity,
and the irradiation time period of each light are changed as
appropriate, accordingly.
(1) First Processing Step
First, with reference to FIGS. 2A and 2B, the binding form of the
fluorescent dyes is described. In the first processing step, during
sample preparation, the first fluorescent dyes are bound to the
first substances. As shown in FIG. 2A, the first fluorescent dye is
bound to the first substance via an intermediate substance that
specifically binds to the first substance. During sample
preparation, the second fluorescent dyes are bound to the second
substances. As shown in FIG. 2B, the second fluorescent dye is
bound to the second substance, also via an intermediate substance
that specifically binds to the second substance. During sample
preparation, the nucleus of each test cell is specifically stained
by the third fluorescent dyes. Here, in a case where the first
substance or the second substance is a gene, a nucleic acid probe
can be used as the intermediate substance. In a case where the
first substance or the second substance is a protein, an antibody
specific to the protein can be used as the intermediate substance.
With respect to the substance that binds to a fluorescent dye, the
target and the number thereof may be changed in accordance with the
analysis purpose.
As schematically shown in FIG. 3A, a large number of the first
fluorescent dyes are bound to one first substance. In FIG. 3A, two
first substances each having the first fluorescent dyes bound
thereto are schematically shown. Similarly, a large number of the
second fluorescent dyes are bound to one second substance. As
described above, each of the first fluorescent dye and the second
fluorescent dye is a fluorescent dye switchable between the
quenched state and the active state by laser light having a
predetermined wavelength.
In the initial state, as schematically shown in FIG. 3A, all the
first fluorescent dyes are in the active state. In FIG. 3A, the
active state is indicated by a black circle. In this state, when
light from the light source 11a is applied to the test cell for a
predetermined time period, all the first fluorescent dyes are
quenched as shown in FIG. 3B. In FIG. 3B, the quenched state is
indicated by a white circle.
Then, when light from the light source 11c is applied to the test
cell for a predetermined time period, a part of the first
fluorescent dyes are activated as shown in FIG. 3C, for example.
Through adjustment of the irradiation time period of the light from
the light source 11c, the proportion of the first fluorescent dyes
to be activated is changed. When light from the light source 11a is
applied to the test cell for a predetermined time period, again,
all the first fluorescent dyes are quenched as shown in FIG. 3B.
Then, when light from the light source 11c is applied to the test
cell for a predetermined time period, again, a part of the first
fluorescent dyes are activated as shown in FIG. 3D, for example. As
shown in FIGS. 3C and 3D, the distribution of the first fluorescent
dyes activated through the activation process each time is
different.
In the first processing step, the first fluorescent dyes are
quenched once, then, activated again, and then, irradiated with
light for excitation, and an image of fluorescence is captured.
Thus, the first image is obtained in a state where the first
fluorescent dyes sparsely emit fluorescence, as shown in FIG. 3C,
for example. The second fluorescent dyes are switchable between the
quenched state and the active state, but in the first processing
step, an image of the second fluorescent dyes is captured in the
initial state, without being quenched. Therefore, the second image
is obtained in a state where all the second fluorescent dyes emit
fluorescence as shown in FIG. 3A.
In the first processing step, the wavelengths of lights emitted
from the light sources 11a, 11b, 11c are 640 nm, 730 nm, and 405
nm, respectively.
As shown in FIG. 4A, in step S101, the processing unit 111 causes
light from the light source 11b to be applied to the test cell at
20 mW for 1.5 seconds, thereby to cause fluorescence to be
generated from the second fluorescent dyes, and causes the image
capturing unit 19 to capture an image of the generated
fluorescence. The processing unit 111 repeats the image capturing
while the light is applied to the test cell, and obtains 100 second
images. It should be noted that, in step S101, 100 second images
are obtained, but the number of images to be obtained is not
limited thereto, and one image may be obtained, for example.
In step S102, the processing unit 111 causes light from the light
source 11c to be applied to the test cell at 1 mW for 1.5 seconds,
thereby to cause fluorescence to be generated from the third
fluorescent dyes, and causes the image capturing unit 19 to capture
an image of the generated fluorescence. The processing unit 111
repeats the image capturing while the light is applied to the test
cell, and obtains 100 third images. It should be noted that, in
step S102, 100 third images are obtained, but the number of images
to be obtained is not limited thereto, and one image may be
obtained, for example.
In step S103, the processing unit 111 causes light from the light
source 11a to be applied to the test cell at 80 mW, thereby to
cause the first fluorescent dyes to be quenched. In step S104, the
processing unit 111 causes light from the light source 11c to be
applied to the test cell at 15 mW for 0.15 seconds, thereby to
activate the first fluorescent dyes. In step S105, the processing
unit 111 causes light from the light source 11a to be applied to
the test cell at 80 mW for 2 seconds, thereby to cause fluorescence
to be generated from the first fluorescent dyes, and causes the
image capturing unit 19 to capture an image of the generated
fluorescence. While the light is applied to the test cell, the
processing unit 111 repeats the image capturing and obtains 100
first images. In step S105, since the light that is the same as
that in step S103 is used, the first fluorescent dyes are quenched
while the light is applied in step S105. Then, an image obtaining
process of the first processing step ends. It should be noted that,
in step S105, 100 first images are obtained, but the number of
images to be obtained is not limited thereto, and one image may be
obtained, for example.
Then, in step S111 shown in FIG. 4B, the processing unit 111
creates diffraction-limited images of the first fluorescent dyes,
the second fluorescent dyes, and the third fluorescent dyes, on the
basis of the first images, the second images, and the third images,
respectively. Hereinafter, the diffraction-limited image of the
fluorescent dyes obtained through quenching and reactivation is
particularly referred to as "reactivation diffraction-limited
image".
As shown in FIG. 5A, the reactivation diffraction-limited image is
created by averaging images obtained by performing quenching and
activation only once as shown in steps S103 to S105 in FIG. 4A.
Thus, the reactivation diffraction-limited image of the first
fluorescent dyes is created by averaging 100 first images obtained
in step S105.
As shown in FIG. 5B, the diffraction-limited image is created by
averaging images obtained without performing quenching and
activation as shown in steps S101 and S102 in FIG. 4A. Thus, the
diffraction-limited image of the second fluorescent dyes is created
by averaging the plurality of the second images obtained in step
S101. The diffraction-limited image of the third fluorescent dyes
is created by averaging the plurality of the third images obtained
in step S102.
With reference back to FIG. 4B, in step S112, the processing unit
111 creates a reference image by superposing the three images
obtained in step S111. The reference image is displayed on a screen
on which a determination result described below is displayed. In
step S113, the processing unit 111 identifies the region of the
nucleus of the test cell on the basis of the diffraction-limited
image of the third fluorescent dyes obtained n step S111.
In step S114, the processing unit 111 obtains the total number of
the first substances. Specifically, as shown in FIG. 5A, the
processing unit 111 calculates the total area of fluorescence
regions in the region of the nucleus of the test cell obtained in
step S113, in the reactivation diffraction-limited image of the
first fluorescent dyes obtained in step S111. Subsequently, the
processing unit 111 divides the calculated total area of the
fluorescence regions by the area of a fluorescence region
corresponding to one first substance and stored in advance in the
storage unit 112, and uses the division result as the total number
of the first substances. It should be noted that how to obtain the
total number of the first substances is not limited to the method
of dividing the total area of the fluorescence regions by a unit
area. For example, the approach shown in FIG. 7 to be used in the
second processing step described below may be applied to 100 first
images, to obtain the total number of the first substances.
With reference back to FIG. 4B, in step S115, the processing unit
111 obtains the total number of the second substances in a similar
manner to that in step S114. That is, the processing unit 111
calculates the total area of the fluorescence regions in the region
of the nucleus of the test cell obtained in step S113, in the
diffraction-limited image of the second fluorescent dyes obtained
in step S111. Subsequently the processing unit 111 divides the
calculated total area of the fluorescence regions by the area of a
fluorescence region corresponding to one second substance and
stored in advance in the storage unit 112, and uses the division
result as the total number of the second substances. The order of
the process of step S114 and the process of step S115 may be
inversed.
In step S116, the processing unit 111 calculates the ratio of the
total number of the first substances to the total number of the
second substances, i.e., "the number of the first substances/the
number of the second substances". For example, in a case where 30
test cells are contained in the captured image, the processing unit
111 calculates the ratio by dividing the total number of the first
substances in the 30 test cells by the total number of the second
substances in the 30 test cells. Then, the analysis process in the
first processing step ends.
In step S116, the processing unit 111 may calculate the ratio by
dividing the number of the first substances in one test cell by the
number of the second substances in one test cell. In this case, the
processing unit 111 obtains the number of the first substances in
one test cell, by averaging the numbers of the first substances
obtained for the respective test cells. Further, the processing
unit 111 obtains the number of the second substances in one test
cell, by averaging the numbers of the second substances obtained
for the respective test cells.
(2) Second Processing Step
In the first processing step, during the image capturing, with
respect to the first fluorescent dyes, the quenching process and
the reactivation process are each performed only once. However, in
the second processing step, with respect to the first fluorescent
dyes, a quenching process, a reactivation process, and an image
capturing process are repeated a plurality of times, whereby the
first images are obtained. In addition, in the second processing
step, bright points are extracted from each obtained first image,
the extracted bright points are classified into groups each
corresponding to a first substance, whereby the number of the first
substances is obtained.
It should be noted that the second processing step is assumed to be
subsequently performed after the image obtaining process and the
analysis process in the first processing step have been performed.
Therefore, in the second processing step, at the start of the image
obtaining process, a state has been established where the first
fluorescent dyes have been quenched through the image capturing
process of the first processing step, i.e., step S105 in FIG. 4A.
In a case where the processes of the second processing step are
independently performed, i.e., not following the first processing
step, step S101 to S103 in FIG. 4A are added before step S121 in
FIG. 6A, step S113 in FIG. 4B is added in the latter stage of step
S132 in FIG. 6B, and step S115 in FIG. 4B is added in the latter
stage of step S133 in FIG. 6B.
As shown in FIG. 6A, in step S121, the processing unit 111 causes
light to be applied from the light source 11c to the test cells at
15 mW for 0.15 seconds, thereby to activate the first fluorescent
dyes. In step S122, the processing unit 111 causes light to be
applied from the light source 11a to the test cells at 80 mW for
2.25 seconds, thereby to cause fluorescence to be generated from
the first fluorescent dyes, and causes the image capturing unit 19
to capture an image of the generated fluorescence. While the light
is applied to the test cells, the processing unit 111 repeats the
image capturing and obtains 100 first images. In step S122, while
the light is applied, the first fluorescent dyes are quenched.
In step S123, the processing unit 111 determines whether the
obtainment of the first image has ended. The processing unit 111
repeats the processes of steps S121 and S122 a predetermined number
of times. Here, the processes of steps S121 and S122 are repeated
29 times. In this manner, the processing unit 111 obtains 3000
first images, which is the total of 100 first images obtained in
step S105 in FIG. 4A and 2900 first images obtained by repeating
the processes of steps S121 and S122, 29 times.
As shown in FIG. 6B, in step S131, the processing unit 111 creates
a super-resolution image of the first fluorescent dyes.
As shown in FIG. 7, the super-resolution image is created on the
basis of the first images obtained through steps S103 to S105 in
FIG. 4A and steps S121 to S123 in FIG. 6A. Specifically, for each
first image, bright points of fluorescence are extracted through
Gauss fitting. Accordingly, on a two-dimensional plane, coordinates
of each bright point is obtained. Here, for each fluorescence
region on a first image, if matching with a reference waveform is
obtained in a predetermined range through Gauss fitting, a bright
point region having a width corresponding to this range is assigned
to each bright point. With respect to a bright point in a
fluorescence region that matches, at one point, with the reference
waveform, a bright point region having a lowest-level width is
assigned. Thus obtained bright point regions of the respective
bright points are superposed for all the first images, whereby a
super-resolution image is created.
Thus, the super-resolution image of the first fluorescent dyes is
created by the bright points being extracted from the 3000 first
images obtained through steps S103 to S105 in FIG. 4A and steps
S121 and S122 in FIG. 6A, and then by the bright point regions of
the extracted bright points being superposed.
With reference back to FIG. 6B, in step S132, the processing unit
111 creates a reference image by superposing the super-resolution
image of the first fluorescent dyes obtained in step S131 and the
diffraction-limited image of the second fluorescent dyes and the
diffraction-limited image of the third fluorescent dyes obtained in
step S111 in FIG. 4B. The reference image is displayed on the
screen on which a determination result described below is
displayed.
In step S133, the processing unit 111 obtains the number of the
first substances. Specifically, as shown in FIG. 7, the processing
unit 111 classifies the bright points extracted at the creation of
the super-resolution image in step S131, into groups each
corresponding to one first substance. That is, first, the
processing unit 111 maps all the bright points extracted from the
3000 first images, onto a coordinate plane. Next, the processing
unit 111 scans the coordinate plane with a reference region having
a predetermined width, and refers to the number of bright points
contained in the reference region. Further, the processing unit 111
extracts the position of a reference region in which the number of
bright points contained in the reference region is greater than a
threshold and greater than in the surrounding area, and classifies
the group of the bright points contained in the reference region at
the extracted position, into a group that corresponds to a first
substance. It should be noted that the method for classifying
bright points into groups each corresponding to a first substance
is not limited thereto. The bright points may be classified into
groups each corresponding to a first substance through another
clustering approach.
Here, as described with reference to FIGS. 3A to 3D, a large number
of the first fluorescent dyes are bound to one first substance. In
addition, as shown in FIGS. 3C and 3D, the first fluorescent dyes
bound to one first substance are sparsely activated, and the
distribution of the first fluorescent dyes activated through the
quenching process and the activation process is different each
time. Thus, the positions of the bright points that correspond to
the first substances are slightly shifted for each first image.
However, by grouping the bright points as described above, bright
points that are close to each other and that are based on a
plurality of the first fluorescent dyes bound to one first
substance are classified into one group.
In step S133 in FIG. 6B, further on the coordinate plane, the
processing unit 111 identifies the region of the nucleus of each
test cell obtained in step S113, and counts the number of groups
contained in the region of the nucleus of the test cell. Thus, the
processing unit 111 obtains the counted number of the groups, as
the number of the first substances. Here, when a plurality of the
test cells are contained in the first image, the number of the
first substances is obtained, for example, by averaging the numbers
of the first substances obtained for the respective test cells.
Thus, since the region of the nucleus of each test cell is
identified in step S113 in FIG. 4B on the basis of the images
captured by the image capturing unit 19, the region of the nucleus
of the test cell can be superposed on the bright points of the
first fluorescent dyes on the images in step S133, and thus, the
bright points of the first fluorescent dyes can be smoothly
extracted for each region of the nucleus of the test cell.
Accordingly, the number of the first substances can be smoothly
obtained.
In step S134, the processing unit 111 calculates the ratio of the
number of the first substances obtained in step S133, to the number
of the second substances in one test cell, i.e., "the number of the
first substances/the number of the second substance". The number of
the second substances in one test cell is obtained by dividing the
total number of the second substances obtained in step S115 in FIG.
4B, by the number of the nuclei in the test cells. Then, the
analysis process in the second processing step ends. It should be
noted that the number of the first images obtained in step S122 in
FIG. 6A is not limited to 100, and may be another number.
In the description below, in a case where the number of the first
substances and the number of the second substances for each nucleus
are to be obtained on the basis of the total number of the first
substances and the total number of the second substances obtained
in steps S114 and S115 of the first processing step, a process of
dividing the total number of the first substances and the total
number of the second substances by the number of the nuclei in the
test cells is performed, similarly to step S134.
As described above, when the activation process is performed after
the inactivation process of quenching the first fluorescent dyes
has been performed, only a part of the first fluorescent dyes bound
to each first substance are activated. In addition, it could happen
that the first fluorescent dyes not having been activated by the
activation process last time are activated by the activation
process this time. Therefore, by repetition of the inactivation
process, the activation process, and the image capturing process a
plurality of times, the first fluorescent dyes can be caused to
emit light evenly, and at the same time, fluorescence of the first
fluorescent dyes can be caused to be dispersed in each first image.
Thus, from each first image, bright points based on the first
fluorescent dyes can be smoothly extracted. Then, by the
classification of the extracted bright points into groups each
corresponding to a first substance, the number of the first
substances can be counted. Accordingly, the number of the first
substances in the test cells can be accurately counted.
It should be noted that, in the first processing step and the
second processing step, it is necessary to adjust the intensity of
light for activation emitted from the light source 11c so that the
first fluorescent dyes can be detected at one-molecule level. In
the case of Embodiment 1, activation efficiency was increased in
proportion to the product of the intensity of the activation light
and the exposure time period of the activation light, and the
activation efficiency was saturated at a certain level. The
activation efficiency means the proportion of the first fluorescent
dyes activated through one activation process, in the quenched
first fluorescent dyes. The activation efficiency for accurately
detecting the first fluorescent dyes is not higher than 20%, and
preferably not higher than 10%. If the intensity of the activation
light and the exposure time period of the activation light are
adjusted so as to realize a desired value of the activation
efficiency, the first fluorescent dyes can be accurately
detected.
In a case where the activation efficiency is set to be low as
above, in order to activate all the first fluorescent dyes and
perform detection thereof, the greater the number of times of
repeating the quenching and activation, the better. However, a
greater number of times of repeating results in a long measurement
time period. Thus, in Embodiment 1, in order to make the
measurement time period as short as possible, the total number of
times of repeating the quenching and the activation through the
first processing step and the second processing step is set to 30.
The number of times of repeating the quenching and the activation
is not limited to 30, and can be set to a desired number of times
in consideration of the activation efficiency and the measurement
time period. When there is no need to detect the first fluorescent
dyes at one-molecule level, the activation efficiency may be higher
than or equal to 50%. The activation efficiency is determined
depending on the density in the test cells.
(3) Experiment
Next, an experiment performed by the inventors is described. In the
experiment, for convenience, a type of dye that is switchable
between the quenched state and the active state was used as the
second fluorescent dyes. However, since the second fluorescent dyes
are not quenched in the first and second processing steps in
Embodiment 1 as described above, a non-switchable type of
fluorescent dye may be used. As such a type of second fluorescent
dye, a fluorescent dye such as Cy2 can be used, for example.
<Creation of FISH Stained HER-2 Sample>
Experiment samples were created through the following steps.
By use of Ventana Inform Dual ISH HER-2 kit (manufactured by Roche
Diagnostics K.K.), staining was performed on HER-2 gene
amplification positive calu-3 and HER-2 gene amplification negative
MCF7 cells on HER-2 Dual ISH 3-in-1 Control Slide (Ventana).
[FFPE Sample Preparation Step]
The control slide was dried on Dry Block Bath THB (AS ONE) at
65.degree. C. for 20 minutes. Ez Prep was placed on the slide and
deparaffinization was performed at 75.degree. C. for 5 minutes.
This operation was repeated 5 times, and then the slide was
immersed in Reaction Buffer. Dry Block Bath THB was set at
90.degree. C., CC2 was dropped thereto, and then, conditioning was
performed for 10 minutes. CC2 was added as appropriate so as to
prevent the slide from drying. This operation was performed 3
times, and then, the slide was immersed in Reaction Buffer for 4
minutes. This operation was repeated 3 times. On the slide, ISH
Protease II was dropped by 80 .mu.L, a cover glass was placed
thereon, and the slide was subjected to an enzymatic treatment for
16 minutes in a moist chamber placed in an incubator at 37.degree.
C.
The slide was immersed in 2.times.SSC for 4 minutes 3 times to be
washed. HybReady and HER-2 DNA cocktail probes were mixed, and the
mixture was dropped by 30 .mu.L on the slide, covered with a cover
glass, and then sealed with paper bond. The slide was placed on Dry
Block Bath THB, and thermal denaturation was performed thereon at
95.degree. C. for 20 minutes. Then, hybridization was performed on
the slide overnight on DryBlock Bath THB at 44.degree. C. The slide
was immersed in 2.times.SSC at 62.degree. C. for 4 minutes to be
washed. This operation was repeated 3 times, and the slide was
immersed in Reaction Buffer. 1% BSA/Reaction buffer was dropped on
the slide by 500 .mu.L, and blocking was performed on the slide for
20 minutes in a moist chamber placed in an incubator at 37.degree.
C. The slide was immersed in Reaction buffer to be washed.
[Staining Step]
Rabbit Anti DNP Antibody and Mouse Anti DIG Antibody were mixed
together, and the mixture was dropped on the slide, covered with a
cover glass, and allowed to react for 20 minutes in a moist chamber
placed in an incubator at 37.degree. C. The slide was immersed in
Reaction Buffer for 3 minutes to be washed. This operation was
performed 3 times. AlexaFluor 647 F(ab').sub.2 fragment of goat
anti-rabbit IgG (H+L) (Life Technologies, A-21246), AlexaFluor 750
GoatAnti Mouse IgG(H+L) (Life Technologies, A-21037), and Hoechst
33342 (Life Technologies, H1399) (100 mg was diluted in PBS 10 mL
and preserved) were diluted by 1000-fold with 1% BSA/Reaction
buffer. The resultant mixture was dropped to the slide by 80 .mu.L,
covered with a cover glass, and allowed to react for 20 minutes in
a moist chamber placed in an incubator at 37.degree. C. The slide
was immersed in TBST for 3 minutes to be washed. This operation was
performed 3 times. The slide was immersed in PBS for 3 minutes to
be washed. This operation was performed 3 times. The slide was
immersed in purified water to be washed. This operation was
performed twice, and the slide was dried for 15 minutes in an
incubator at 37.degree. C.
Alexa Fluor 647 corresponds to the first fluorescent dyes described
above. Alexa Fluor 750 corresponds to the second fluorescent dyes
described above. Hoechst 33342 corresponds to the third fluorescent
dyes described above.
[Image Capture Preparatory Step]
0.04 .mu.m FluoSphere Dark Red (life technology, F8789) was diluted
with PBS, and the mixture was dropped to the slide by 50 .mu.L,
covered with a cover glass, and left still for 10 minutes. The
slide was washed with 500 .mu.L of PBS, a mount medium was dropped
by 50 .mu.L, a cover glass was placed thereon and fixed with
manicure. The composition of the mount medium was as follows. 1M
Tris (pH 7.4) 5 .mu.L, 1M NaCl 1 .mu.L, 25% glucose 40 .mu.L,
2-mercaptoethanol 1 .mu.L, 5000 U/mL Glucose Oxidase 1 .mu.L, 1000
.mu.g/mL catalase 1 .mu.L, H2O 51 .mu.L <Process Result of First
Processing Step>
The processes according to the first processing step were performed
on the sample above. Reference images created in step S112 in FIG.
4B of a sample based on HER-2 gene amplification positive calu-3
are shown in FIGS. 8A to 8D. In FIGS. 8A to 8D, each dotted arrow
indicates the first substance, i.e., HER-2 gene, and each thick
arrow indicates the second substance, i.e., CEP17.
Through the process of the first processing step, the ratio
calculated in step S116 in FIG. 4B was 6.12 in the case of a sample
based on HER-2 gene amplification positive calu-3, and was 0.83 in
the case of a sample based on HER-2 gene amplification negative
MCF7 cells. According to a breast cancer guideline, the ratio
greater than 2.2 means positive, the ratio smaller than 1.8 means
negative, and the ratio not smaller than 1.8 and not greater than
2.2 means borderline. Therefore, through the processes of the first
processing step, a positive sample can be appropriately determined
as positive, and a negative sample can be appropriately determined
as negative.
<Process Result of Second Processing Step>
Next, the processes according to the second processing step were
further performed on the sample above. Reference images created in
step S132 in FIG. 6B of a sample based on HER-2 gene amplification
positive calu-3 are shown in FIGS. 9A to 9D. Reference images
created in step S132 in FIG. 6B in the case of a sample based on
HER-2 gene amplification negative MCF7 cells are shown in FIGS. 9E
to 9G. Also in FIGS. 9A to 9G, similarly to FIGS. 8A to 8D, each
dotted arrow indicates the first substance, i.e., HER-2 gene, and
each thick arrow indicates the second substance, i.e., CEP17.
Through the processes of the second processing step, the ratio
calculated in step S134 in FIG. 6B was 6.42 in the case of a sample
based on HER-2 gene amplification positive calu-3, and was 1.18 in
the case of a sample based on HER-2 gene amplification negative
MCF7 cells. Therefore, also through the second processing step, a
positive sample can be appropriately determined as positive, and a
negative sample can be appropriately determined as negative.
<Comparative Example>
Next, as Comparative Example 1, a process was performed in which,
with respect to a sample based on HER-2 gene amplification positive
calu-3, a reference image was obtained without performing the
quenching and the activation thereon. Reference images created in
Comparative Example 1 are shown in FIGS. 10A to 10D.
At this time, the calculated ratio was 7.48 in the case of a sample
based on HER-2 gene amplification positive calu-3, and was 1.16 in
the case of a sample based on HER-2 gene amplification negative
MCF7 cells. Therefore, also in Comparative Example 1, a positive
sample can be appropriately determined as positive, and a negative
sample can be appropriately determined as negative.
Next, as Comparative Example 2, a process was performed in which,
with respect to a sample based on HER-2 gene amplification positive
calu-3, a reference image was obtained by use of a confocal laser
scanning microscope, without performing the quenching and the
activation thereon. Reference images created in Comparative Example
2 are shown in FIGS. 10E to 10G. In Comparative Example 2, images
of the second substances, i.e., of CEP17 were not obtained.
When the reference images according to the first processing step
shown in FIGS. 8A to 8D are compared with the reference images
according to Comparative Examples 1, 2 shown in FIGS. 10A to 10G,
it is seen that the bright points corresponding to HER-2 gene are
more separated in the first processing step. When the reference
images according to the first processing step shown in FIGS. 8A to
8D are compared with the reference image according to the second
processing step shown in FIGS. 9A to 9D, it is seen that the bright
points corresponding to HER-2 gene are further separated in the
second processing step.
According to the reference images of FIG. 8A to FIG. 9D, even in
the case of a sample based on HER-2 gene amplification positive
calu-3, CEP17 as the second substance is less in number, and is
well separated spatially. Thus, with respect to the second
fluorescent dyes which each bind to CEP17, the fluorescence regions
were identified at high resolution, without through a step of
reactivation after quenching thereof. Thus, with respect to the
second substances for which fluorescence regions can be identified
without through the step of quenching and reactivation, by
obtaining the second image without performing an inactivation
process of quenching the second fluorescent dyes, the process can
be simplified.
<Other Examination>
In the experiment according to the processes of the second
processing step, as shown in the regions surrounded by the squares
in FIGS. 9B and 9D, portions in which bright point regions based on
the first fluorescent dyes were connected in a line shape were
observed. According to examination by the inventors, also when the
other HER-2 gene amplification positive test cells were examined
through the processes of the second processing step, similarly to
FIGS. 9B and 9D, portions in which bright point regions were
connected in a line shape were observed in a super-resolution
image. The reason of this is considered as follows: in association
with progress of breast cancer, amplification of HER-2 gene as the
first substance became significant, the distance between HER-2
genes is reduced, and thus, the bright point regions are shown as
being connected in a line shape. Thus, with respect to breast
cancer, disease condition judgement and therapeutic strategy
decision can be accurately performed by further performing
determination on the basis of information regarding the location of
the first substances, i.e., the distance between the first
substances, together with the determination based on the ratio
described above. This determination is considered to be similarly
applicable to other diseases than breast cancer.
Here, the distance between the first substances is focused.
However, depending on the kind of the first substance, it is
assumed that, in association with progress of the disease condition
or the amplification, the distribution state such as the position,
the size, or the like of the first substances could be changed, in
addition to the distance between the first substances. Therefore,
disease condition judgement and therapeutic strategy decision are
considered to be accurately performed by further performing
determination on the basis of the distribution state of the first
substances.
(4) Display Process in Embodiment 1
In the processes of the first processing step, the total area of
fluorescence regions is divided by the area of a fluorescence
region that corresponds to one first substance with fluorescence,
whereby the number of the first substances is obtained. In this
method, when the number of the first substances is small and the
distance between the first substances is large, the fluorescence
regions of the respective the first substances are separated from
one another in the reactivation diffraction-limited image, and
thus, the number of the first substances can be relatively
accurately obtained. Thus, also according to the processes of the
first processing step, breast cancer negative determination can be
appropriately performed.
However, when breast cancer progresses, and the number of the first
substances increases, the fluorescence regions of the respective
the first substances could overlap one another in the reactivation
diffraction-limited image. Thus, in the processes of the first
processing step, the accuracy of the determination result regarding
breast cancer based on the ratio could be reduced. In contrast to
this, in the processes of the second processing step, even when the
number of the first substances has increased as mentioned above,
the number of the first substances can be obtained with high
accuracy, and thus, appropriate determination regarding breast
cancer can be performed. Thus, in the display process below, first,
the processes of the first processing step is performed to
determine whether or not amplification of the disease marker is
negative, and then, only when the determination result is not
negative, the processes of the second processing step are
performed.
As shown in FIG. 11, in step S141, the processing unit 111 performs
the processes of the first processing step shown in FIGS. 4A and
4B. Accordingly, the processing unit 111 obtains the ratio
indicating the presence/absence of amplification of the first
substances, in step S116 in FIG. 4B. In step S142, the processing
unit 111 performs determination regarding amplification of the
disease marker on the basis of the ratio calculated in step S116 in
FIG. 4B. Specifically, the processing unit 111 determines as
positive when the ratio is greater than 2.2, the processing unit
111 determines as negative when the ratio is smaller than 1.8, and
the processing unit 111 determines as borderline when the ratio is
not smaller than 1.8 and not greater than 2.2.
Subsequently, in step S143, the processing unit 111 determines
whether the determination result in step S142 is negative or not.
When the determination result in step S142 is negative, then, in
step S144, the processing unit 111 causes the display unit 120 to
display, as therapy index information, the ratio indicating the
presence/absence of amplification of the first substances obtained
in the first processing step and the determination result obtained
in step S142. Then, the display process ends. In this case,
determination and display on the basis of the second processing
step are not performed. On the other hand, when the determination
result in step S142 is positive or borderline, the processing unit
111 advances the process to step S145.
In step S145, the processing unit 111 performs the processes of the
second processing step shown in FIGS. 6A and 6B. In step S146, on
the basis of the ratio calculated in step S134 in FIG. 6B, the
processing unit 111 performs determination regarding amplification
of the disease marker. The determination method is the same as in
step S142. As described above, according to the second processing
step, the number of the first substances is accurately counted.
Thus, in step S146, on the basis of the number of the first
substances accurately counted, determination regarding
amplification of the first substances serving as the target
molecules of the molecular target drug is performed. Accordingly, a
more accurate determination result regarding disease condition can
be obtained.
Subsequently, in step S147, the processing unit 111 determines
whether the determination result in step S146 is positive or not.
When the determination result in step S146 is positive, the
processing unit 111 causes, in step S148, the display unit 120 to
display therapy index information including the determination
result obtained in step S146. Then, the display process ends. On
the other hand, when the determination result in step S146 is
negative or borderline, the processing unit 111 advances the
process to step S149.
In step S149, the processing unit 111 determines whether there is a
line-shaped structure of the first substances in the reference
image created in step S132 in FIG. 6B. The line-shaped structure of
the first substances is a structure as shown in the regions
surrounded by squares in FIGS. 9B and 9D. When HER-2 genes, as the
first substances, that have a distance therebetween smaller than a
threshold are consecutively present by a predetermined number, the
processing unit 111 determines that there is a line-shaped
structure of the first substances in the reference image.
When the processing unit 111 has determined that there is a
line-shaped structure of the first substances, the processing unit
111 changes, in step S150, the determination result obtained in
step S146 to positive. On the other hand, when the processing unit
111 has determined that there is no line-shaped structure of the
first substances, the processing unit 111 advances the process to
step S148 without changing the determination result obtained in
step S146. Then, the display process ends.
In each of steps S142 and S146, determination regarding breast
cancer is performed on the basis of the ratio of the number of the
first substances and the number of the second substances. However,
determination regarding breast cancer may be performed by comparing
the number of the first substances for each nucleus with a
threshold. However, in a case where the balance between the number
of the first substances and the number of the second substances
changes in accordance with progress of the disease condition as
described above, if disease condition judgement is performed also
with reference to the number of the second substances together with
the number of the first substances, the accuracy of disease
condition judgement can be increased.
As described above, with respect to breast cancer, in association
with abnormal cell division, the number of HER-2 genes as the first
substances increases in the nucleus of a test cell. Accordingly,
the balance between the number of HER-2 genes and the number of
CEP17s changes. Thus, as in the processes described above, by
performing determination regarding amplification of the disease
marker on the basis of the ratio between the number of the first
substances and the number of the second substances, it is possible
to more accurately determine the presence/absence of amplification
of the disease marker. The value indicating the balance between the
number of the first substances and the number of the second
substances is not limited to the ratio, and may be the difference
between the number of the first substances and the number of the
second substances, for example.
In the flow chart shown in FIG. 11, when the determination result
according to the second processing step is not positive, the
process is advanced to step S149. However, the process may be
advanced to step S149 irrespective of the determination result. In
addition, although the determination result as negative or
borderline is changed to positive when there is a line-shaped
structure, an indication that there is a line-shaped structure may
be added to the determination result, without the determination
result being changed.
As shown in FIGS. 12A and 12B, a screen 200 displayed on the
display unit 120 in the display process includes a result region
210 and a comment region 220. In the result region 210, information
obtained through the processes of the first processing step or the
second processing step is displayed. Specifically, in the result
region 210, therapy index information including the number of the
first substances per test cell, the ratio, and the determination
result regarding the disease condition relevant to the first
substances; other therapy index information indicating the
presence/absence of a line-shaped structure; and a reference image
are displayed. In the comment region 220, supplementary description
regarding the content of the result region 210 is displayed.
The screen 200 shown in each of FIGS. 12A and 12B is the one
obtained when the processes of the second processing step have been
performed. In FIG. 12A, no line-shaped structure is present in the
test cell, and in FIG. 12B, line-shaped structures are present in
the test cell.
On the screen 200 shown in FIG. 12B, a message indicating that
there is a line-shaped structure in the comment region 220 is
displayed. As shown in FIGS. 12A and 12B, since therapy index
information including a determination result is displayed on the
screen 200, the doctor or the like can perform highly accurate
disease condition diagnosis without being required to perform
complicated work such as counting bright points through visual
observation. Since the doctor or the like is not required to be
well skilled in making disease condition diagnosis, variation in
diagnosis made by the doctor can be suppressed. Since the ratio
between the number of the first substances and the number of the
second substances is displayed in the result region 210, the doctor
or the like can make a therapeutic strategy decision by referring
to this ratio. It should be noted that the therapy index
information to be displayed is not limited to those shown in FIGS.
12A and 12B, and the indication of the number of the first
substances may be omitted, or the indication of the determination
result may be omitted, for example.
When the determination result in the first processing step is not
negative, a reference image obtained in the second processing step
is displayed in the result region 210. This reference image has
been created on the basis of the super-resolution image of the
first fluorescent dyes, and thus, is a highly accurate image
indicating the distribution state of bright points of the first
fluorescent dyes. Thus, the doctor or the like can confirm the
disease condition in more detail by referring to the distribution
state of the bright points in this image.
In a case where the determination result in the first processing
step is negative and the process of the second processing step is
skipped, the numerical values, the determination result, and the
reference image based on the processes of the first processing step
are displayed in the result region 210, and the column of the
line-shaped structure is masked.
As described above, in test cells of a patient who does not have
breast cancer, the number of HER-2 genes is small and HER-2 genes
are less likely to be close to one another. Thus, also through the
image analysis in the first processing step, the number of HER-2
genes in the test cells can be accurately counted, and the fact
that amplification of the first substances is negative can be
accurately determined. Thus, in a case where the determination in
the first processing step is negative, even if the processes of the
second processing step are skipped, no problem is caused in the
determination result. In addition, in this case, by the processes
of the second processing step being skipped, the determination
result can be provided quickly to the doctor or the like. In a case
where the determination in the first processing step is not
negative, the processes of the second processing step which allow
more accurate counting of the number of HER-2 genes are performed,
and the determination is made. Thus, a highly accurate
determination result can be presented to the doctor or the
like.
2. Embodiment 2
In Embodiment 2, the second fluorescent dyes are also quenched and
activated similarly to the first fluorescent dyes.
As shown in FIG. 13, in Embodiment 2, steps S201 and 202 are added
immediately before step S101 in the process of the first processing
step in FIG. 4A. Accordingly, the second fluorescent dyes which
bind to the second substances are also quenched in step S201 and
then activated in step S202, and then, an image of fluorescence is
captured in step S101. Through the process of step S101, the second
fluorescent dyes are quenched. In this case, in step S111 in FIG.
4B, also with respect to the second substances, a reactivation
diffraction-limited image is obtained similarly to the first
substances, and then, in step S112, the obtained reactivation
diffraction-limited image is superimposed with other images.
Accordingly, in the reference image, fluorescence regions of the
second substances are more separated than in Embodiment 1. As a
result, the accuracy of the number of the second substances
obtained in step S115 in FIG. 4B is increased. The order of the
processes of steps S201, S202, and S101 and the processes of steps
S103 to S105 may be inversed.
As shown in FIG. 14A, in Embodiment 2, step S211 to S213 are added
before step S121 in the process of the second processing step in
FIG. 6A. Also with respect to the second fluorescent dyes which
bind to the second substances, the process of activation in step
S211 followed by image capturing and quenching in step S212 is
repeated by the number of times specified in step S213, whereby a
plurality of second images are obtained.
In this case, as shown in FIG. 14B, step S221 is added in the
latter stage of step S133 in FIG. 6B. In step S131, also with
respect to the second substances, similarly to the first
substances, bright points are extracted with respect to the second
images, a super-resolution image is obtained, and then, in step
S132, the obtained super-resolution image is superimposed with
other images. Accordingly, in the reference image, the resolution
of the bright point regions of the second substances is
significantly increased. In addition, in step S221, similarly to
the obtainment of the number of the first substances in step S133,
also with respect to the second substances, bright points are
classified into groups, and the number of the second substances is
obtained. Accordingly, the accuracy of the number of the second
substances is increased. As a result, the accuracy of the ratio
calculated in step S134 is also increased.
In Embodiment 2, quenching and activation are also performed with
respect to the second fluorescent dyes. Thus, the distribution of
the second substances can be displayed with higher resolution than
in Embodiment 1.
In a case where amplification of the second substances in the test
cells becomes significant in association with progress of the
disease condition, two second substances could be close to each
other. In such a case, if all the second fluorescent dyes bound to
the two close second substances emit fluorescence at the same time,
it becomes difficult to capture an image with fluorescences
separated from one another. In Embodiment 2, also with respect to
the second fluorescent dyes bound to the second substances, the
step of quenching and reactivation is performed, thereby to capture
an image of fluorescence. Thus, even in a case where amplification
of the second substances becomes significant in association with
progress of the disease condition, it is possible to capture an
image in which fluorescences based on the second fluorescent dyes
are separated from one another. Accordingly, the accuracy of
disease condition judgement can be increased.
In a case where the super-resolution image is obtained with respect
to the second substances as in Embodiment 2, the location of the
second substances and the distribution state of the second
substances may be obtained, similarly to the first substances. The
location of the second substances corresponds to the distance
between the second substances, for example. Depending on the kind
of the second substance, it is assumed that, in association with
the progress of the disease condition or the amplification, the
distance between the second substances and the distribution state
such as the position, the size, or the like of the second
substances could be changed. Therefore, it is considered that,
further on the basis of the distance between the second substances
and the distribution state of the second substances, disease
condition diagnosis and therapeutic strategy decision can be
accurately performed.
<Modification>
As described above, in a case where the second fluorescent dyes are
also quenched and activated, it is possible to use, as the types of
the first fluorescent dye and the second fluorescent dye,
switchable fluorescent dyes for which lights having different
wavelengths are used for excitation, but for which a light having
the same wavelength is used for activation. In this Modification,
as the types of the first fluorescent dye and the second
fluorescent dye, such fluorescent dyes are used.
In this case, as shown in FIG. 15A, with respect to the processes
of the first processing step, steps after step S201 in FIG. 13 are
changed. Lights having different wavelengths are applied to the
test cells in steps S301 and S302, respectively, whereby the second
fluorescent dyes and the first fluorescent dyes are quenched. Then,
in step S303, light having a predetermined wavelength is applied,
whereby the second fluorescent dyes and the first fluorescent dyes
are activated at the same time. Then, in steps S304 and S305,
lights which excite the first fluorescent dyes and the second
fluorescent dyes are applied to the test cells respectively,
whereby the first image and the second image are obtained. Through
the processes of steps S304 and S305, the first fluorescent dyes
and the second fluorescent dyes are quenched, respectively.
The process of the second processing step shown in FIG. 14A is
changed as shown in FIG. 15B. In step S311, light having a
predetermined wavelength is applied, whereby the second fluorescent
dyes and the first fluorescent dyes are activated at the same time.
Then, lights which excite the second fluorescent dyes and the first
fluorescent dyes are applied to the test cells in step S312 and
S313, respectively, whereby the second image and the first image
are obtained. Through the processes of steps S312 and S313, the
second fluorescent dyes and the first fluorescent dyes are
quenched, respectively. The process of activation, image capturing,
and quenching in step S311 to S313 is repeated by the number of
times specified in step S314, whereby a plurality of first images
and a plurality of second images are obtained.
As described above, since the activation of the quenched first
fluorescent dyes and second fluorescent dyes is performed in a
single step, the process is simplified. In particular, in a case
where quenching and reactivation are repeated by a large number in
order to obtain a super-resolution image, if the activation of the
first fluorescent dyes and the second fluorescent dyes is performed
in a single step, the process can be significantly simplified.
3. Embodiment 3
In Embodiment 3, a part of the optical system is changed, compared
with that in Embodiment 1, and the position of each bright point in
the optical axis direction of the image capturing unit 19 is
obtained by the processing unit 111.
As shown in FIG. 16A, in the cell analyzer 10, a beam expander 19c
and a phase plate 19d are added to the image capturing unit 19.
Fluorescence generated from a sample passes through the beam
expander 19c, the phase plate 19d, and the condenser lens 19a, in
order, and then an image of the fluorescence is captured by the
image pickup device 19b.
The phase plate 19d is disposed at the Fourier plane, and has an
action of modulating a point spread function such that two focal
points appear on the light receiving surface of the image pickup
device 19b. Fluorescence generated from one fluorescent dye forms
an image at two focal points on the light receiving surface of the
image pickup device 19b as a result of the action of the phase
plate 19d. At this time, as shown in FIG. 16B, the two focal points
rotate on the light receiving surface in accordance with the
position of the light emission point of fluorescence in the optical
axis direction of the image capturing unit 19. That is, the angle
between the straight line connecting the two focal points and a
straight line serving as a reference varies on the light receiving
surface of the image pickup device 19b, in accordance with the
position of the light emission point of fluorescence in the optical
axis direction.
For example, fluorescences generated from fluorescent dyes at two
different positions in the optical axis direction of the image
capturing unit 19 on the glass slide 22 are each split into two by
the phase plate 19d, and applied to the light receiving surface of
the image pickup device 19b. At this time, as shown in FIG. 16B,
for example, with respect to one fluorescent dye, the straight line
connecting the two focal points on the light receiving surface
forms an angle of +.theta.1 relative to the reference line, and
with respect to the other fluorescent dye, the straight line
connecting the two focal points on the light receiving surface
forms an angle of +.theta.2 relative to the reference line.
Therefore, if the angle between the straight line connecting two
focal points and the reference line is obtained, the position of
the fluorescent dye in the optical axis direction can be
obtained.
Specifically, similarly to the second processing step, the
processing unit 111 performs Gauss fitting on the first images
obtained by repeating quenching and activation, to extract bright
points, and further, obtains the brightness of each extracted
bright point. Next, the processing unit 111 pairs two bright points
that have similar brightness and the distance between which is in a
predetermined range. Subsequently, the processing unit 111 performs
fitting with respect to the paired two bright points against a
two-bright-point template stored in advance in the storage unit
112. Then, the processing unit 111 determines two bright points
that are fitted with a certain accuracy or higher, as bright points
resulting from the splitting of fluorescence generated from one
fluorescent dye by the phase plate 19d.
Subsequently, the processing unit 111 sets the midpoint of the
paired two bright points on the light receiving surface, as the
position on the two-dimensional plane at the image capture angle of
the fluorescent dye. On the basis of the angle between the
reference line and the straight line connecting the two bright
points paired as described above, the processing unit 111
determines the position of the fluorescent dye in the optical axis
direction of the image capturing unit 19. In this manner, on the
basis of the positions on the two-dimensional plane and the
positions in the optical axis direction, the processing unit 111
specifies coordinate points of a plurality of fluorescent dyes in
the three-dimensional coordinate axes, superposes the specified
coordinate points for all the first images, and thereby creates a
three-dimensional super-resolution image.
Further, the processing unit 111 classifies the specified
coordinate points into groups each corresponding to a first
substance, thereby to obtain the number of the first substances in
the test cells. In grouping of the coordinate points, for example,
a predetermined reference space is caused to scan a
three-dimensional coordinate space, the position of a reference
space in which the number of coordinate points is greater than a
threshold and in which the number of bright points is greater than
in the surrounding area thereof is extracted, and then, the group
of bright points contained in the reference space at the extracted
position is classified into a group that corresponds a first
substance.
Subsequently, the processing unit 111 obtains the range of the
nucleus in the three-dimensional space of each test cell.
Specifically, the processing unit 111 causes the objective lens 17
to move in the optical axis direction of the image capturing unit
19, and obtains images at a plurality of different focus positions
in the optical axis direction. At this time, the region in which
fluorescence based on the third fluorescent dyes is detected
corresponds to the nucleus, and the region in which fluorescence
based on the third fluorescent dyes is not detected corresponds to
a substance other than the nucleus, i.e., corresponds to cytoplasm.
The processing unit 111 obtains the contour of the nucleus from the
region in which fluorescence has been detected, for each of the
obtained plurality of images. Then, on the basis of each focus
position and the contour of the nucleus at that position, the
processing unit 111 obtains the range of the nucleus in the
three-dimensional space. Examples of the third fluorescent dye
include a 7-AAD, DAPI, SYTOX-based fluorescent dye, a SYTO-based
fluorescent dye, propidium iodide, and the like, in addition to
Hoechst 33342 described above. Then, the processing unit 111
obtains, as the number of the first substances, the number of the
groups contained in the range of the nuclei of the test cells.
For example, the three-dimensional super-resolution image is
obtained as shown in FIGS. 17A and 17B. In each figure, the X-Y
plane is the two-dimensional plane at the image capture angle, and
the Z-axis direction is the optical axis direction of the image
capturing unit 19. FIGS. 17A and 17B are actually-obtained
three-dimensional super-resolution images of samples whose results
of determination regarding breast cancer are negative and positive,
respectively. When the three-dimensional super-resolution images of
FIGS. 17A and 17B are viewed in the Z-axis direction and the Y-axis
direction, the images as shown in FIGS. 17C and 17D can be
obtained, respectively.
When a three-dimensional super-resolution image is created, a
screen 300 as shown in FIG. 18 is displayed on the display unit 120
in the display process. Similarly to the screen 200 shown in FIGS.
12A and 12B, the screen 300 includes a result region 310 and a
comment region 320. In the result region 310, images obtained when
a three-dimensional super-resolution image is viewed in the Z-axis
direction and in the Y-axis direction are displayed. In the result
region 310, three-dimensional super-resolution images as shown in
FIGS. 17A and 17B may be displayed.
According to Embodiment 3, with respect to the first fluorescent
dyes, a three-dimensional super-resolution image can be obtained
that allows identification of the position in the optical axis
direction of the image capturing unit 19 as well as the position on
the two-dimensional plane at the image capture angle. Thus, bright
points that are overlapped with one another on the two-dimensional
plane can also be separated and extracted. Accordingly, the number
of the first substances can be further accurately counted, and a
more accurate determination result can be presented to the doctor
or the like. In addition, by referring to the three-dimensional
super-resolution image, the doctor or the like can also understand
the distribution of the first substances in the optical axis
direction, and thus, can perform disease condition judgement and
therapeutic strategy decision more accurately.
The distance between the first substances and the distribution
state of the first substances may be obtained on the basis of the
three-dimensional super-resolution image. The three-dimensional
super-resolution image allows more accurate understanding of the
distance between the first substances and the distribution state of
the first substances. Thus, disease condition judgement and
therapeutic strategy decision can be more accurately performed. In
addition, also with respect the second substances, a
three-dimensional super-resolution image may be obtained, and on
the basis of the obtained three-dimensional super-resolution image,
the distance between the second substances and the distribution
state of the second substances may be obtained. Also in this case,
the distance between the second substances and the distribution
state of the second substances can be more accurately understood.
Thus, disease condition judgement and therapeutic strategy decision
can be more accurately performed.
In Embodiments 1 to 3, the disease as the therapy target is breast
cancer, and the first substance serving as therapeutic strategy
judgement index is HER-2. However, not limited thereto, another
disease may be set as the therapy target, and the first substance
serving as the therapeutic strategy judgement index may be another
substance in accordance with the target disease. The second
substance may also be another substance in accordance with the
target disease. In a case where the first substance is another
substance, different from the embodiments described above, it could
be assumed that the first substances are decreased than that in a
normal state, depending on the disease condition. The approaches of
Embodiments 1 to 3 can be also used in detection of decrease of the
first substances as appropriate. Thus, similarly to the case where
HER-2 is the target, decrease of the first substances can be
accurately detected. In addition, also when the second substances
increase or decrease depending on the disease condition, the
approaches of Embodiments 1 to 3 can be similarly applied.
* * * * *
References